diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # Revision history for http3
 
+## 0.1.1
+
+* Removing a debug logging to stdout.
+
 ## 0.1.0
 
 * QPACK encoder now supports the dynamic table.
diff --git a/Network/HTTP3/Context.hs b/Network/HTTP3/Context.hs
--- a/Network/HTTP3/Context.hs
+++ b/Network/HTTP3/Context.hs
@@ -80,9 +80,7 @@
     abortWith :: ApplicationProtocolError -> E.SomeException -> IO ()
     abortWith aerr se
         | isAsyncException se = E.throwIO se
-        | otherwise = do
-            print se
-            abortConnection conn aerr ""
+        | otherwise = abortConnection conn aerr ""
 
 isAsyncException :: E.Exception e => e -> Bool
 isAsyncException e =
diff --git a/Network/QPACK/HeaderBlock/Encode.hs b/Network/QPACK/HeaderBlock/Encode.hs
--- a/Network/QPACK/HeaderBlock/Encode.hs
+++ b/Network/QPACK/HeaderBlock/Encode.hs
@@ -296,7 +296,7 @@
                 ridx <- toInsRelativeIndex ai <$> getInsertionPoint dyntbl
                 let ins = Duplicate ridx
                 encodeEI wbuf2 True ins
-                qpackDebug dyntbl $ putStrLn $ (show ins) ++ " = " ++ show ai
+                qpackDebug dyntbl $ putStrLn $ show ins ++ " = " ++ show ai
                 nai <- tailDuplication dyntbl
                 qpackDebug dyntbl $ putStrLn $ "Duplicate: " ++ show ai ++ " -> " ++ show nai
 
diff --git a/Network/QPACK/Table/Dynamic.hs b/Network/QPACK/Table/Dynamic.hs
--- a/Network/QPACK/Table/Dynamic.hs
+++ b/Network/QPACK/Table/Dynamic.hs
@@ -537,7 +537,7 @@
 
 ----------------------------------------------------------------
 
-canInsertEntry :: DynamicTable -> Entry -> Maybe (AbsoluteIndex) -> IO Bool
+canInsertEntry :: DynamicTable -> Entry -> Maybe AbsoluteIndex -> IO Bool
 canInsertEntry DynamicTable{..} ent mai = do
     let siz = entrySize ent
     tblsiz <- readTVarIO tableSize
diff --git a/http3.cabal b/http3.cabal
--- a/http3.cabal
+++ b/http3.cabal
@@ -1,6 +1,6 @@
 cabal-version:      2.4
 name:               http3
-version:            0.1.0
+version:            0.1.1
 license:            BSD-3-Clause
 license-file:       LICENSE
 maintainer:         Kazu Yamamoto <kazu@iij.ad.jp>
diff --git a/test/QPACK/QIF2Spec.hs b/test/QPACK/QIF2Spec.hs
--- a/test/QPACK/QIF2Spec.hs
+++ b/test/QPACK/QIF2Spec.hs
@@ -35,22 +35,22 @@
     describe "QIF server" $ do
         it "handles dynamic table of 0-bytes" $ do
             let size = 0
-            E.bracket (setup server size) (teardown) $
+            E.bracket (setup server size) teardown $
                 \_ -> runClient size
     describe "QIF server" $ do
         it "handles dynamic table of 256-bytes" $ do
             let size = 256
-            E.bracket (setup server size) (teardown) $
+            E.bracket (setup server size) teardown $
                 \_ -> runClient size
     describe "QIF server" $ do
         it "handles dynamic table of 512-bytes" $ do
             let size = 512
-            E.bracket (setup server size) (teardown) $
+            E.bracket (setup server size) teardown $
                 \_ -> runClient size
     describe "QIF server" $ do
         it "handles dynamic table of 4096-bytes" $ do
             let size = 4096
-            E.bracket (setup server size) (teardown) $
+            E.bracket (setup server size) teardown $
                 \_ -> runClient size
 
 runClient :: Int -> IO ()